Those of you with multiple dogs/pets... how do you make individual time for them, and keep them from feeling left out?

Most of my life I've only had one dog. I'm only 21... and my older dog is 9 years old... so she's been my only dog.

And now I have a puppy, a cat, and a horse in addition to her. My cat loves attention, but he doesn't NEED it, and my horse is happy as long as she has a buddy and plenty of grass/hay... so it's really my puppy that eats up my time. She gets to go more places with me since she's also my Service Dog in Training...

But I feel bad because I leave my baby girl, my truly heart dog, behind. I sleep next to her every night... but often, due to work and school schedules, can't take her on individual walks or do a lot of individualized stuff with her.... and her eyes when I take Arya somewhere and leave her behind... I'm probably anthropomorphizing way too much... but it makes me feel horrible.